An Overview of Laser Engraving Craftsmanship

Laser engraving, also known as laser etching, is a type of surface processing craft. Similar to printing and offsetting, they all print text or patterns on products. However, compared to the latter, laser engraving has faster marking speed; more beautiful patterns; higher resolution; less wear and tear; better precision; and lower cost. Laser engraving refers to using the optical energy of a laser beam to cause chemical and physical changes in the surface material to engrave traces, or to burn away part of the material to reveal the desired engraved patterns or text. According to the engraving method, it can be divided into dot matrix engraving and vector cutting.

• Dot Matrix Engraving: Similar to high-definition dot matrix printing, the laser head swings left and right each time to engrave a line composed of a series of dots. Then, the laser head moves up and down at the same time to engrave multiple lines, eventually forming the entire graphic or text.
• Vector Engraving: This is usually performed on the outer contour line of a graphic or text. This mode is commonly used for piercing and cutting through materials such as wood, paper, and acrylic. It can also be used to mark various surfaces.

Characteristics of Artisanal Craftsmanship

Principle

1. Utilizing the high-intensity focused laser beam emitted by the laser, the material is oxidized at the focal point to process it;
2. The marking effect is achieved by vaporizing the surface material to reveal the underlying material, or by using the light energy to cause chemical and physical changes in the surface material to leave traces, or by burning away part of the material to reveal the desired engraved patterns or text.

Performance

The performance of a laser engraving machine is mainly determined by its engraving speed, engraving strength, and light spot size.

• Engraving Speed: This refers to the speed at which the laser head moves, usually expressed in IPS (inches per second). High speed brings high production efficiency. Speed can also be used to control the depth of cutting or engraving. With a specific laser strength, the slower the speed, the deeper the cutting or engraving will be. The engraving speed can be adjusted through the control panel of the laser engraving machine or by using the computer's printing drive program. The adjustment range is from 1% to 100%, with an adjustment interval of 1%.
• Engraving Strength: The greater the strength, the deeper the cutting or engraving.
• Light Spot Size: This can be adjusted using lenses with different focal lengths. Lenses with smaller focal lengths are suitable for high-resolution engraving. Lenses with larger focal lengths are suitable for lower resolution engraving, but they are the best choice for vector engraving. The standard configuration is usually a 2.0-inch lens, with a light spot size in the middle, suitable for various situations.

Applicable Materials

Bamboo products, organic glass, metal plates, glass, stone, crystal, acrylic, paper, double-color board, anodized aluminum, leather, plastic, epoxy resin, polyester resin, spray-painted metal.

Parameters and Technological Processes

The engraving effect of the laser engraving machine mainly undergoes debugging from the following aspects:

• Current Intensity:
  • When engraving metal materials, the current intensity is large, generally above 10.
  • When engraving non-metallic materials, the current intensity is small, generally around 9.5-10.
  • The current intensity has a significant impact on engraving non-metallic materials. If the current is too large, it will damage the product surface, such as burning, engraving with bubbles, etc. If it's too small, the pattern will not be clear and will lack depth.
• Focal Length:
  • When engraving metal materials, the distance from the focal point should generally be closer.
  • When engraving non-metallic materials, it can deviate from the focal point, especially when engraving translucent buttons. One must deviate from the focal point by 3-5mm.
• Impact of Engraving Parameters on the Effect:
  • Increasing precision
  • Increasing depth
  • Increasing engraving speed
  • Decrease jump delay time
  • Decrease void vector step interval time

Laser Engraving Technological Process

1. Pre-cleaning: This is mainly used to remove oil and dirt from the surface of the material to ensure the clean surface required for laser engraving.
2. Engraving: The process of generating marks on the surface of the workpiece using a laser beam.
3. Post-processing after Carving: After the carving work is completed, the machine needs to be stopped and the carved parts need to be disassembled and the carving machine needs to be cleaned.

Common Problems and Improvement Methods

1. Problem: Engraving with bubbles
   Improvement method: Reduce the current intensity, increase the engraving speed, or adjust the distance between the focal point and the surface of the material.
2. Problem: Engraving with burn marks
   Improvement method: Reduce the current intensity or reduce the engraving speed.
3. Problem: Engraving with uneven depth
   Improvement method: Adjust the distance between the focal point and the surface of the material, or adjust the engraving speed.
4. Problem: Engraving with unclear patterns
   Improvement method: Increase the current intensity or increase the engraving speed.
5. Problem: Engraving with incomplete patterns
   Improvement method: Increase the current intensity, increase the engraving speed, or increase the effective vector step.
6. Problem: Engraving with excessive heat generation
   Improvement method: Increase the cooling rate, reduce the current intensity, or reduce the engraving speed.
7. Problem: Engraving with poor adhesion
   Improvement method: Increase the surface roughness of the material, increase the current intensity, or reduce the engraving speed.

Note: When encountering problems during the engraving process, try to adjust the relevant parameters step by step to find the optimal solution. If the problem persists, consider seeking professional technical support.

Conclusion

Laser engraving is a versatile and precise surface processing technique that offers numerous advantages over traditional printing and marking methods. Its ability to engrave on various materials with high speed, excellent resolution, and minimal wear and tear makes it an ideal choice for numerous industries, including packaging, signage, and promotional products. Understanding the principles and characteristics of laser engraving and the parameters that affect its performance is crucial for achieving optimal results. By following the proper technological processes and addressing common problems, one can ensure consistent, high-quality engraving that meets their specific needs.